Companies will have to designate cybersecurity coordinators and follow clear rules for incident response.

The attack on the Toronto Transit Commission follows another on the Ann Arbor Transportation Authority last week.

Broadly, the administration is also formulating a national cybersecurity strategy and looking at more regulations.

DHS Secretary Alejandro Mayorkas and Deputy Attorney General Lisa Monaco spelled out the plans at separate events.

It's the second set of requirements TSA has issued since the momentous Colonial Pipeline ransomware attack.

The company's response put on display broader Hill concerns about the private sector's ransomware safeguards.